Optimization of shell-and-tube heat exchangers conforming to TEMA standards with designs motivated by constructal theory

• A design method of heat exchangers motivated by constructal theory is proposed.
• A genetic algorithm is applied and the TEMA standards are rigorously followed.
• Three cases are studied to illustrate the advantage of the proposed design method.
• The design method will reduce the total cost compared to two other methods.

A modified optimization design approach motivated by constructal theory is proposed for shell-and-tube heat exchangers in the present paper. In this method, a shell-and-tube heat exchanger is divided into several in-series heat exchangers. The Tubular Exchanger Manufacturers Association (TEMA) standards are rigorously followed for all design parameters. The total cost of the whole shell-and-tube heat exchanger is set as the objective function, including the investment cost for initial manufacture and the operational cost involving the power consumption to overcome the frictional pressure loss. A genetic algorithm is applied to minimize the cost function by adjusting parameters such as the tube and shell diameters, tube length and tube arrangement. Three cases are studied which indicate that the modified design approach can significantly reduce the total cost compared to the original design method and traditional genetic algorithm design method.